Dental flosses have long been used effectively to clean the spaces between the teeth and under the gum margin. One example of a dental floss is disclosed in U.S. Pat. No. 3,800,812. To increase the effectiveness of the floss, some flosses have included certain medicinal ingredients such as fluoride compounds to protect the tooth enamel from acid attack. Bactericides have also been used in connection with dental floss to inhibit periodontal disease. The medicinal components have typically been applied as a coating to the preformed dental floss.
When used properly, dental floss has been found to be effective in inhibiting tooth decay and gum disease and is recommended by dentists in the daily dental hygiene program. Dental floss often has the disadvantage of causing the gums to bleed, which discourages its use by some people. Bleeding of the gums may be caused by the friction of the floss against the gum surface and by the rough texture of the floss.
There have been numerous attempts in the art to produce a superior dental floss that is convenient to use and is less prone to cause bleeding of the gums. Other dental flosses have been provided with a dentifrice component. For example, U.S. Pat. No. 3,830,246, U.S. Pat. No. 3,897,795, U.S. Pat. No. 4,215,478 and U.S. Pat. No. 3,771,536 disclose dental flosses which are impregnated with a fluoride compound to aid in the delivery of the fluoride to the tooth surface between adjacent teeth. U.S. Pat. No. 4,033,365 discloses a floss designed to retain flavorants over a long period of time through the use of non-wax polymeric coatings containing spray-dried flavor particles.
U.S Pat. No. 3,943,949 discloses a dental floss-like material in the form of a bundle of natural or synthetic fibers, such as nylon. The floss is coated with various waxes, including microcrystalline wax, to reduce the friction of the floss against the tooth surface. The wax coating is disclosed as containing a spray-dried flavorant to be dispersed during use.
As exemplified by the above-noted patents, flossing is an extremely important adjunct to proper dental hygiene. Many of the dental flosses presently on the market have received limited consumer acceptance. The lack of consumer acceptance of any single dental floss on the market is due in part to the propensity of dental floss to cause gingival bleeding. In addition, dental floss is generally considered difficult and uncomfortable to use. The consumer dissatisfaction with some dental flosses is caused by the relatively high coefficient of friction (COF) of the floss.
Because prior art flosses have such high friction coefficients, the user must apply substantial downward force to pull the floss between the contact points of the teeth. Unfortunately, the typical user will pull downward with sufficient force to allow the floss to pass between the teeth and snap against the gum surface, causing irritation and possible bleeding of the gum tissue. Some of the difficulty in pulling the floss between the teeth is the result of the thickness of the floss compared to the spaces between the teeth. In order to reduce the risk of gum injury, many manufacturers have coated the floss with wax or other lubricant to reduce the friction coefficient and increase the ease with which it can be inserted between the teeth.